A witless narcissist mysteriously elected president! Conspiracy theories abound! Nuclear annihilation at hand! Only a last-minute investigation and impeachment can save the country!

There will also be singing. And shrink rays.

That’s what Adult Swim has in store for viewers Sunday at midnight with the unexpected return of one of the properties that helped launch Turner’s late-night comedy block 18 years ago, when the original creative team and voice cast of Harvey Birdman: Attorney at Law, including Stephen Colbert and Gary Cole, reunite for an all new special, Harvey Birdman: Attorney General.

Like many of the original Adult Swim series, Harvey Birdman raided the Hanna-Barbara cartoon empire of the 1960s and 70s – now owned by Turner, a division of Time Warner (recently acquired by ATT) – for laughs that appealed to both the nostalgia and cynicism of GenX, then in their 20s and 30s. The flying superhero Birdman, along with assorted sidekicks and villains, were transplanted to a law firm handling matters involving other cartoon characters: for example, a custody battle involving boy adventurer Jonny Quest, or a case where Shaggy and Scooby are busted for possession. The high concept plots were just springboards for bizarre and hilarious character interactions involving Harvey (voiced by Cole), his megalomaniac boss Phil Ken Sebben (Colbert), associate Peter Pottamous (Chris Edgerly) and many others.

The original series ran for four seasons through 2007. It helped establish the distinct brand of Adult Swim and defined a bleak but hilarious approach to adult-oriented animated comedy that can be seen today in everything from Rick and Morty to Bojack Horseman. Now, after a ten-year absence, the show’s creators Erik Richter and Michael Ouweleen have reunited the original cast and crew for a special that reprises the show’s trademark madcap surrealism for a new, more surreal cultural moment.

I had a chance to talk to Richter and Ouweleen ahead of Sunday’s big “reunion” episode. Our conversation has been edited for length and clarity.

Rob Salkowitz, Forbes contributor: When you first launched Harvey Birdman and the original batch of Adult Swim shows, did you have any inkling that the approach and style would have this much staying power?

Erik Richter: Yes, Michael visited a psychic in the late 80s who predicted all of this. Sorry, no. Absolutely not. Everything has been a shock. [Turner] made this block and allowed Matt (Maiellaro) and Dave (Wills, co-creators of Aqua Teen Hunger Force), Adam (Reed, of Sealab 2021 and now Archer) and us make all this stuff. We had no idea if anyone would watch it.

Michael Ouweleen: We knew it might resonate but it didn’t feel fated to succeed. Our mandate was to give new meaning to old characters, experiment, keep it cheap and see where it goes.

ER: They gave us three inches of rope to hang ourselves.

RS: Stephen Colbert was part of the original voice cast – was he even on the Daily Show back in 2000? How did you find him originally? And how hard was it to get him to come back for the reunion?

ER: He was around [back in 2000]. We knew him from previous work doing improv. We cast him from that. I think he read for Harvey [as well as Phil Ken Sebben, the character he plays]. Maybe we have that on a CD somewhere.

MO: Stephen was in early days with The Daily Show [when we started]. We had him from then to beginning of Colbert Report [in 2006]. We thought we were doing him a favor by killing his character so he could go do big famous-guy stuff, but he seemed disappointed so we brought him back a few episodes later.

ER: In terms of getting him back for the special episode, let’s just say he didn’t do it for the money. Once we were able to accommodate his schedule, he was very nice to find the time to record. He even does a song in two character voices. He’s a true improv person, in the moment, open to suggestions. He’s great.

MO: The whole cast is that way. They’re very spontaneous. When we do our script reads, if we can get a laugh out of them, it’s like making a kid laugh. It’s very satisfying to have everyone on the same wavelength like that.

RS: The original audience for the show in the early 2000s grew up with those Hanna-Barbara cartoons, so you were able to get a lot of mileage out of the in-jokes and nostalgia. Today, 20-30 year-olds might not have the same frame of reference. Does that change how you approach the show creatively?

ER: Totally. Harvey Birdman: Attorney General leans less on the secondary H-B characters and focuses on the core cast, partly because we love the core cast and didn’t need to use old characters. We got great notes from the younger team members at Adult Swim that we’re just the right amount of confusing and familiar.

RS: Was it weird to come back to this series after a ten-year gap, when you’ve both been doing other things?

MO: Erik and I made a lot of stuff for fun over the years in lots of different formats. No one has seen it. We all wanted to do a longer project together again, we just never thought it would be Harvey Birdman. That’s why we killed him off [in the last episode of the original series]!

ER: The whole new episode was just an excuse to hang out together.

RS: Is there anything timely or relevant about doing Harvey Birdman: Attorney General at this particular moment?

MO: (laughs) it seems like there is, but there isn’t. The idea for Attorney General was from our boss. It gobsmacked us because it was so perfect. The whole premise of humor in Harvey Birdman is impostor syndrome – this guy who is essentially a superhero finds himself working in a law office, like, “what’s going on?” Everyone is trying to keep up and say this is fine, this is the way it’s supposed to be, when in fact everything is just wrong.

Today, we’re all Harvey Birdman. We all have this feeling of things aren’t the way they used to be. We’re confronting these rapidly changing norms and feel like we’re the only ones who notice. So we’re giving vent to that, letting that tension out.

I am an author, consultant and educator with a professional interest in the business implications of new media and a personal passion for comics and visual communication. My 2012 book Comic-Con and the Business of Pop Culture (McGraw-Hill) looks at trends in entertainment, m...